Various wanted and unwanted substances or residues may be removed from objects or substrates using various methods. For instance, chemical solvents may be used to remove unwanted residues from machinery, unwanted particles from products, or otherwise. Solvents may also be used to extract residues or substances from chemical compositions, products, or materials. For instance, a solvent may be used to separate a particular chemical compound from a mixture of chemical compounds. However, many of the solvents typically used by industry are not environmentally friendly. In fact, many of the solvents are hazardous materials and are expensive to use, maintain, control, and dispose of.
As one example, solvents are used to remove the build-up of solid and liquid petroleum residues and substances from substrates such as processing equipment. The build-up of oil residues such as asphalt and asphalt-related liquids (e.g., tar, pitch, and tack) on processing equipment utilized in petroleum and chemical processing, storage, and transport industries, as well as equipment used in highway and road construction, has long been problematic. After a certain level of build-up occurs, the equipment is often no longer capable of being used for its intended purpose. Accordingly, it is typically necessary to clean such equipment. Diesel fuel or a similar type of fuel has been used in the past for cleaning construction equipment. However, the use of these solvents has largely fallen into disfavor due to heightened environmental concerns. See e.g., Federal Water Pollution Control Act Amendments of 1972 (PL 92-500) Section 311(b)(1).
Another alternative is to employ organic solvents. Such solvents also pose potential environmental concerns. For instance, chlorinated solvents such as 1,1,1-trichloroethane or methylene chloride may be used to remove petroleum residues or substances from substrates. Moreover, notwithstanding any potential benefits associated therewith, these solvents are typically less than fully effective in removing petroleum residue. More specifically, these solvents are often not able to remove hard-to-dissolve petroleum residue fractions such as asphaltenes. Accordingly, these fractions are typically removed by employing labor-intensive efforts that are often time-consuming and expensive.
As another example, there is a current increasing interest in extracting wanted tar sand oil from its naturally occurring ores. Such ores are substantial underutilized sources of fossil fuels, particularly, for example, in Venezuela, Canada, and the United States. As crude oil reserves become relatively heavier, the need and consequent demand for recovering bitumen fractions from inorganic substrates (e.g., tar sands) increases.
Examples of methods currently employed in the extraction of tar sands involve the use of hot water, organic solvents, or petroleum distillates. During hot water extraction, emulsions are formed that are often difficult to break and to efficiently separate bitumen from water. These processes usually result in the generation of relatively high quantities of wastewater, termed “extraction tailings”. Methods of wastewater treatment are often needed to allow a production site to attempt to comply with environmental regulations. Extractions with organic solvents or petroleum distillates often utilize materials of relatively high capital value to obtain bitumen of a lower capital value. Moreover, solvent extraction typically requires significant expenditures of equipment and energy to separate extracted bitumen from the organic solvent. As a result, it is extremely difficult on a commercial scale to employ extraction methods employing organic solvents.
The treatment and remediation of asphaltenic deposits occurring in different places in the production, refining, and transportation of crude oil is also desirous. Many crude oils are prone to form asphaltenic deposits. These deposits are detrimental to the productivity of the reservoir (as they clog the porosity of the pay zone), throughput of the pipeline, efficiency of the desalter and gas-liquid separator, and the storage capacity of a storage tank. Currently these asphaltenic deposits are either removed mechanically, or by employing expensive and environmentally irresponsible solvents.
Therefore, it is desirous to develop and use compositions and methods for removing residues or substances from substrates without the employment of expensive manual processes or expensive, and often environmentally hazardous, organic solvent extraction processes.